CASE II. When interest multiplied by the time exceeds the principal. 1. At what rate per cent. must $125, be put to interest to gain $37.50 in 6 years. Ans. 5 per ct. 2. At what rate per cent. will $480 yield, $90 interest in 3 years, 1 month, and 15 days? Ans. 6 per ct. 3. If $225 gain $108 in 8 years, what is the rate per cent.? Ans. 6 per cent. 4. At what rate per cent. must $120 be on interest to amount to $133.20 in 16 months. Ans. 81 per cent. 5. At what rate per cent. must $280 be on interest to amount to $411.95 in 6 years? Ans. 7 per cent. CASE II. 1. Suppose $1000, at 4 per cent per annum, amount to $1281.25. How long was it at interest? Ans. 6 years 3 mos. 2. In what time will $1600 amount to $2048 at 4 per cent. per annum? CASE III. Ans. 7 years. 1. In what time will the interest of $600 be equal to the principal at 6 per cent.? Ans. 16 years 8 mos. GENERAL RULE. Divide 100 by the given per centage, and the quotient will be the time in years; if there be a remainder, multiply it by 12, and divide by the rate per cent. 1. For months, thus, 6)100 4 12 16 yrs. 6)48(8 months. 2. At 5 per cent., in what time will double itself at interest? any sum of money Ans. 20 years. 3. At 4 per cent. in what time will any sum of money double itself, at interest? Ans. 25 years. 4. At 6 per cent, in what time will any sum of money treble itself at interest? Ans. 50 years. 5. In what time will the interest of $240, at 6 per ct., be treble the principal? Ans 50 years. 6. A certain property valued at $1500 rents for $132 annually, required the rate of interest? Ans. 8 per ct. INSURANCE. MARINE INSURANCE. The subjects of Marine insurance are, ships, merchandise, freight, &c. The following examples will clearly illustrate the principles of Marine Insurance; Real Estate, or Property In surance. 1. Suppose Ezekiel Dorsey, of Baltimore, shipped on board the brig Nimble, Farrell, master; and consigned to David Dunham, Commission Merchant, Liverpool, to sell for his account: 120 bales cotton, cost 1000 barrels Flour at $5.00, Shipping expenses paid, $6735.00 5000.00 265.00 Amount of shipment and expenses, $12000.00 Before the brig sails, Mr. Dorsey is anxious to have his property insured. Now admitting the rate of insurance to be 1 per cent. premium, and the cost of the policy $1.25 cts. How is the amount to get insured obtained, so as to cover all expenses accurately? RULE. AS 100 less the rate of premium is to 100, so is the sum of cost, charges and policy to the amount required, to get insured Cost and charges 100-11/ = 98: 100 :: $12000.00 12001.25: $12184.01 The amount to get insured, to cover all expenses; hence, Mr. Dorsey would have to pay to the insurance company $184 01. REAL ESTATE. 2. My property in Baltimore is worth $30,000, for what amount must I get it insured, so as to cover cost and charges, insurance being 1 per cent. premium. Policy $1.25. Ans. $30,304.30-of which $304.30 is to be paid to the insurance company. MERCHANDISE. 3. Effected insurance on my Warehouse and Merchandise therein, which cost me $18,000; what sum must I get it insured for, the insurance being 3 per cent., policy, $1.25. Ans. $18,557.99—of which the Underwriters receive $557.99. 'CASE II. When a Commission Merchant ships a cargo, to his correspondent, and therefore cost, charges, premium and policy, are all included. RULE.-Add To of the rate of commission to unity, multiply the sum by the rate of insurance, and call the product b, then as 100 less b: 100 more the rate of commission the sum of the cost, charges, and policy, to the amount sought, which is to be insured. 4. York and M'Allister, Commission Merchants, New Orleans, shipped on board the brig Orleans, Lewis, master, and consigned to Lewis Laroque, London, for his account, 920 bales of cotton, cost, Paid shipping expenses, Effected insurance of the invoice amount by the American Insurance Company, at 4 per cent., policy $1 25. Ans the amount. to get insured to cover all expenses, is $71,024.33. Amount of insurance at 4 per cent. is Commission on the whole, $67,642.22 at 5 per cent. is $64,534.00 266.00 $2842.22 } 3382.11 5. What sum must a policy be taken out for, to cover $2475, when the premium is 10 per ct. Ans. $2750. 6. What is the premium on $896, at 12 per cent. Ans. $107.52. 7. A certain company own a cotton factory in Pittsburgh, valued at $26,250 for what sum must a policy be taken out, to cover cost and charges at 123 per cent.? Ans. $30,000. COMMISSION. 1. What is the commission on $850 at 6 per cent.? Ans. $51. 2. Calculate the commission on $37,702.46 at 5 per cent.? Ans. $1885.12. 3. The sales made by an Auctioneer amount to $209,723; what is his commission at 5 per cent.? Ans. $10,486.15. 4. An Auctioneer's commissions at 5 per cent. on sundry sales in the city of New York, in 1839, amounted to $13,279.58, required the amount of sales made? Ans. $265,591.60. 5. A merchant having $1728 in the Chesapeake Bank of Baltimore, wishes to withdraw 15 per cent.; how much will remain? Ans. $1468.80. DISCOUNT Is an allowance made on a bill, or any other debt not yet become due for prompt payment. The discount taken from the principal leaves the present worth, or value of a bill, when discounted. Q. By having the present worth, how is the discount obtained? A. Subtract the present worth from the principal, and the remainder will be the discount. RULE. To find the present worth at 6 per cent., if the time be for years or months; as 100 plus half the months is to 100, so is the given sum to the present worth. 1. What is the present worth of $1333.20, due 1 year 2. What is the discount of $133,30, due 1 year, 10 3. What is the present worth of a note for $520, due 5 years hence? 4. What is the discount on the above mentioned note, for $520, due 5 years hence? Ans. $400. Ans. $120. 5. What is the present worth of $775.50 due in 4 years, at 5 per cent. per annum? 6. What is the discount of $802.50 one year hence? Ans. $646.25. at 7 per cent. due Ans. $52.50. 7. What is the discount on a note of $117.60, due 1 year hence, at 12 per cent? Ans. $12.60. 8. What is the present worth of $1350, due 5 years, 10 months hence? Ans. $1000. |